A twist on a familiar tale awaits you in the countryside around Novigrad.
The Witcher 3: Little Red
Northeast of Novigrad is a little village called Beanston. Enter and look for some villagers having a pow wow about their bandit troubles. Approach and speak to them, agreeing to assist with their problem, to start the quest.
You need to wait until sunset, when Little Red and her bandits attack. I'd save beforehand, if I were you.
When Little Red arrives she chats with you; you can then opt to let her do what she wants to do in return for a monetary reward, or honour your original contract.
If you elect to battle Little Red, beware: she's a werewolf. It's very important to take out the other bandits first, so get some distance between you and the beast and use Yrden, Axii or Aard to keep her at bay while you duel with her band.
Little Red herself is best taken down with standard werewolf tactics - Cursed Oil, Devil's Puffball and Igni. She'll often dart away into the fields to hide from you; don't be tempted to follow, where she can ambush you. Don't forget to switch to your silver blade once you've finished killing the humans.
When Little Red is down take out any further bandits who might be in other parts of the village, and speak to Bertram for your reward. Loot Little Red for her diary.